How Does Lexical Binding Affect the 'this' Keyword in ES6 Arrow Functions?

Lexical Binding of "this" in ES6 Arrow Functions

Arrow functions in ES6 are renowned for their unique lexical binding behavior of "this." Unlike other JavaScript functions where "this" is dynamically bound, arrow functions maintain a lexical scope, assigning "this" to the same value as its enclosing context.

To illustrate this concept, consider the following code:

var testFunction = () => {
  console.log(this)
};
testFunction();

Contrary to traditional JavaScript behavior where "this" would refer to the global object (window), arrow functions capture the "this" value of the enclosing context. In this example, "this" would refer to the global scope (window) since testFunction is defined outside any object.

Furthermore, lexical binding ensures that "this" remains consistent throughout the lifetime of the arrow function. Consider the following example:

function Person(){
  this.age = 0;

  setInterval(() => {
    this.age++; // |this| properly refers to the person object
  }, 1000);
}

var p = new Person();

Here, the arrow function captures the "this" value of the Person object, allowing it to access and modify its properties (in this case, incrementing the age property). This behavior ensures that "this" always refers to the correct context, regardless of how the arrow function is called or the execution context changes.

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